Printed circuit boards in which the circuit conductors are fixed may be rapidly mass produced. However there is no known system in use for the production of a single prototype or experimental printed circuit board without going through the expensive and laborious photographic process using masking, photographic exposure, resist techniques and the like with multiple step etching.
The applicant has devised a relatively small, compact computer aided printer-etcher unit to facilitate the expeditious, simplified and rapid manufacture of such single prototype or experimental printed circuit board.
The applicant is aware of a number of U.S. patents which are directed to the utilization of a computer aided device (CAD) as a variable input device to both automate and reduce the time and effort necessary to accomplish the production of printed circuit boards integrated circuits or the like.
U.S. Pat. No. 3,567,914 is directed to an automated manufacturing system which deals with the manufacture of printed circuits and discloses a system which eliminates the hand method of layout by integrating a general purpose computer to create a master record of manufactured wiring data and the use of that data by wire routing control data feed to the manufacturing process to create a wired assembly. The use of such a manufacturing system eliminates the necessity of a designer preparing a master drawing or layout of the desired configuration of the conductor paths by hand where the designer is forced to consider every connection necessary in the paths which are available to make the conductor runs prior to the process of plating copperconductor strips or depositing copper foil on various types of laminate or base material to achieve the conductor layout.
U.S. Pat. No. 3,601,590 teaches, in an automated system, the feeding of artwork information from a coordinate read-out table into a digital computer which computer sends such data to the automated layout drafting table to reproduce the artwork information on master mats by a rotary tool mechanism. The production of master mats is employed in the manufacture of miniature electronic circuits. It eliminates a number of steps for transposing the circuits from the engineering and design circuit to the production equipment circuit. The system has application to circuits which are produced through photographic processes, reduced in size from the original master mats with the masters being produced on synthetic master mat material from original circuit concepts provided on drafting paper.
U.S. Pat. No. 4,477,484 is directed to an automated apparatus for determining the initiation, projection and quality electroless plated blind holes or through holes in printed circuit panels. The system uses a test coupon for monitoring the plating having a sensitized initiation conductivity zone and sensitized through hole walls in which the test coupon is measured periodically as to resistivity to determine the start or termination of electroless plating.
U.S. Pat. No. 4,496,607 teaches the use of a computer programmed to move an XY table in a manner to allow a laser beam to melt the surface of the substrate in a pattern of 10 centimeter long parallel lines to create a printed circuit or other electrically conductive circuit on an insulator board. The laser beam melts a tracing of the circuit onto the dielectric while simultaneously impacting metal particles into the trace molten tracks.
U.S. Pat. No. 4,600,996 employs a computer aided design system for drawing a mask, using a mask drawing apparatus to produce circuit patterns for large scale integrated (LSI) circuits by electron beams and in turn controlling a mask inspection apparatus to determine whether the circuit patterns are correctly drawn by the mask drawing apparatus.
From the above patents, it can be seen that computers or data processors have broad application in the design field and computer aided design (CAD) systems have been changing the manner in which electronic designing is accomplished. Such systems allow schematics and artwork to be entered directly from the keyboard into the process of manufacturing of the prototype. In the manufacture of printed circuits, the engineering process remains about the same. Engineers prototype their designs to verify the schematics under the laborious process of depositing resist material onto metal surfaces with the resist being impervious to the chemicals used in the etch phase of the operation. Where, several resist/etch steps are necessary the process is complicated and time consuming. The latter steps involve significant time and moderate expense.
It is therefore an object of the present invention to provide an apparatus for producing prototype printed circuit boards quickly and inexpensively which may be controlled and facilitated via a printer or a plotter output of a CAD system to produce a one-to-one scale version of the desired printed circuit on a thin metal film which may be moved quickly through an etcher integrated to the printer and in which, the printer deposits a resist pattern correlated to the design circuit directly on the thin metal film.